Support AWS Storage w/ HELM template (#337)

* Migrate config from configmap to secret. Add support for AWS Storage Config.

* Add checksome for secret as pod annoation to ensure pod rotates if we update secret.

* Move aws_storage_configs to storage_configs. Move local storage options under a local_storage key.

* Allow specification of storage_config directly as yaml in values.yaml

* Fix syntax for _helpers.tpl